Task 20 - Motor spinning at different rates using PWM

To the right is an image of the Fritzing diagram (breadboarding) - the same as Tasks 18 & 19.



 


 Below it is an image of the actual ET-MINI DC-MOTOR board.
On it is mounted the motor (which is bidirectional), circuitry known as an H-Bridge (for protecting the circuitry connected to it from any induction spikes), 2 direction-indicating LEDs
(L & R), & 2 photo-interrupters labelled 
OPA & OPB (for detecting pulses for measuring motor speed etc).



 




IN this task, we attempt to regulate the motor speed using Pulse Width Modulation (PWM).

This will involve inputting a pulse at varying intervals - the longer the interval the slower the speed.
Clearly, the input pulses must be frequent enough to keeping the motor spinning, but not so frequent as to cause the motor to hit its maximum speed.

The video shows the motor in action, starting slowly & speeding up.